JP2021138877A - Vibration-proof rubber composition - Google Patents

Abstract

To provide a vibration-proof rubber composition exhibiting such high stable attenuation performance that any loss tangent tanδ obtained in dynamic viscoelasticity measurement in a wide temperature range of 0°C, 20°C and 40°C even at a low frequency of 5 Hz is 0.4 or more, and any difference between the loss tangents tanδ on those conditions is 0.40 or less.SOLUTION: A vibration-proof rubber composition contains component A composed of a butyl-based rubber, component B composed of an amorphous α-olefin copolymer, and component C composed of at least one of a hydrogenated non-polar hydrocarbon resin and a terpene-based hydrocarbon resin, in which a mass ratio A:B of the component A to the component B is 90:10 to 65:35.SELECTED DRAWING: None

Description

The present invention relates to a rubber composition for vibration isolation.

Anti-vibration rubber, which exhibits stable anti-vibration properties in a wide temperature range and frequency range, can be used in various applications such as building anti-vibration, vehicle or automobile anti-vibration, precision equipment anti-vibration, and household electrical appliances. It is required for vibration isolation of (for example, washing machines, refrigerators, air conditioners, etc.).

For example, Japanese Patent Application Laid-Open No. 2009-173906 (Patent Document 1) describes a highly dampened rubber composition containing a halogenated butyl rubber as a main component and a non-polar alicyclic saturated hydrocarbon resin and a reactive alkylphenol resin. Disclose.

Japanese Unexamined Patent Publication No. 2010-144142 (Patent Document 2) contains a butyl rubber as a main component, a non-polar alicyclic saturated hydrocarbon resin, a predetermined liquid polymer, and a predetermined nitrogen adsorption specific surface area of 50 m ² / g or less. Discloses a high damping rubber composition containing an inorganic filler of the above and a component of a vulcanizing agent.

Japanese Unexamined Patent Publication No. 2002-187987 (Patent Document 3) describes (A) butyl rubber, (B) other elastomers, (C) tackifier resin, (D) vulcanizing agent and / or cross-linking agent, and (E) vulcanization. It contains an accelerator and / or an activator as a main component, and the content of the component (A) is 50 to 100 parts by weight, the content of the component (B) is 0 to 50 parts by weight, and the content of the component (C) is. Disclosed is a rubber composition having 1 to 50 parts by weight (here, the total amount of the components (A) and (B) is 100 parts by weight).

Japanese Patent Application Laid-Open No. 2005-179525 (Patent Document 4) describes 100 parts by mass of the polymer (A) having a glass transition temperature in the range of −80 to 0 ° C. and a solubility parameter in the range of 7.5 to 8.5. The glass transition temperature is in the range of 10 to 60 ° C., the solubility parameter is 8.5 or more, and the solubility parameter is 8. Disclosed is a rubber composition for vibration isolation, which comprises 5 to 50 parts by mass of a polymer (C) having 5 or more as an essential component.

Japanese Patent Application Laid-Open No. 2012-82388 (Patent Document 5) describes a structural unit (i) derived from 15-75 mol% 4-methyl-pentene and 25-85 mol% α-olefin (where 4-methyl). It consists of the proportion of the structural unit (ii) derived from -1-pentene), and the ultimate viscosity measured at 135 ° C. in decalin is in the range of 0.1 to 5.0 dL / g, and gel permission chromatography. 4-Methyl-1-pentene α in the range of 1.0 to 3.5 in the ratio (molecular weight distribution; Mw / Mn) between the weight average molecular weight (Mw) and the number average molecular weight (Mn) measured by -Disclosure of anti-vibration materials containing at least an olefin copolymer.

Japanese Unexamined Patent Publication No. 2009-17396 Japanese Unexamined Patent Publication No. 2010-144142 Japanese Unexamined Patent Publication No. 2002-187987 Japanese Unexamined Patent Publication No. 2005-179525 Japanese Unexamined Patent Publication No. 2012-82388

In the conventional anti-vibration rubber composition, in the dynamic viscoelasticity measurement, the lower the frequency, the lower the loss tangent tan δ, and the higher the temperature, the lower the loss tangent tan δ. There is a problem that it is difficult to have anti-vibration performance (damping performance). Further, in order to keep the loss tangent tan δ at high temperature high, a method of shifting the glass transition temperature of the rubber composition to around room temperature (for example, 25 ° C.) is used. In such a method, for example, a wide temperature range of 0 to 40 ° C. is used. There is a problem that the change in the loss tangent tan δ is large and it is difficult to exhibit the anti-vibration performance except at a limited temperature.

For example, if there is a large change in the loss tangent tan δ over a wide temperature range of 0 to 40 ° C, there is a problem that the vibration isolation performance changes due to temperature changes due to changes in the external environment (seasonal changes, etc.) or heat generation inside the equipment. .. Therefore, in order to facilitate the design of buildings, vehicles or automobiles, precision equipment, household electric appliances, etc., the value of the loss tangent tan δ is large and its change (that is, the difference between the loss tangent tan δ) over a wide temperature range. There is a demand for the development of anti-vibration rubber compositions with a small temperature.

However, in any of Patent Documents 1 to 5, high damping performance (eg, in dynamic viscoelasticity measurement) under conditions of a wide temperature range (eg 0 ° C, 20 ° C, and 40 ° C) even at low frequencies (eg 5 Hz). No rubber composition has been obtained in which the obtained loss tangent tan δ is 0.40 or more, and the difference between the loss tangent tan δ under these conditions is 0.40 or less).

Therefore, in order to solve the above problem, the present invention has a loss tangent tan δ of 0.40 obtained by dynamic viscoelasticity measurement in a wide temperature range of 0 ° C., 20 ° C., and 40 ° C. even at a low frequency of 5 Hz. It is an object of the present invention to provide a rubber composition for vibration isolation which exhibits a high and stable damping performance in which the difference between the loss tangent tan δ under these conditions is 0.40 or less.

The anti-vibration rubber composition according to one aspect of the present invention comprises an A component composed of a butyl rubber, a B component composed of an amorphous α-olefin copolymer, a hydrogenated non-polar hydrocarbon resin, and a terpene-based carbonized product. It contains a C component composed of at least one of hydrogen resins, and the mass ratio A: B of the A component and the B component is in the range of 90:10 to 65:35.

The anti-vibration rubber composition has a loss tangent tan δ of 0.40 or more and a loss tangent tan δ obtained by dynamic viscoelasticity measurement in a wide temperature range of 0 ° C., 20 ° C., and 40 ° C. even at a low frequency of 5 Hz. It is possible to provide a rubber composition for vibration isolation showing a high and stable damping performance in which the difference between the loss tangent tan δ under these conditions is 0.40 or less.

[Rubber composition for vibration isolation]
The anti-vibration rubber composition of the present embodiment comprises an A component composed of a butyl rubber, a B component composed of an amorphous α-olefin copolymer, and a hydrogenated non-polar hydrocarbon resin and a terpene hydrocarbon resin. It contains at least one C component, and the mass ratio A: B of the A component and the B component is in the range of 90:10 to 65:35. The anti-vibration rubber composition of the present embodiment has a high loss tangent tan δ of 0.40 or more obtained by dynamic viscoelasticity measurement in a wide temperature range of 0 ° C., 20 ° C., and 40 ° C. even at a low frequency of 5 Hz. Shows damping performance. In addition, in this specification, the notation of "X to Y" indicating a range means that the value of X and Y is included.

(Component A)
The anti-vibration rubber composition of the present embodiment contains an A component made of a butyl rubber from the viewpoint of good damping characteristics at low temperatures. Butyl-based rubber has good damping characteristics even at low temperatures because the peak of its loss tangent tan δ exists in the temperature range of 0 ° C. or lower. Here, the "butyl rubber" refers to a rubber composed of butyl and a butyl derivative, and from the above viewpoint, butyl rubber (hereinafter, also referred to as IIR), halogenated butyl rubber (hereinafter, also referred to as X-IIR) and the like are preferable. Can be mentioned. Further, examples of the halogenated butyl rubber include chlorinated butyl rubber (hereinafter, also referred to as Cl-IIR) and brominated butyl rubber (hereinafter, also referred to as Br-IIR). From the viewpoint of shortening the vulcanization time, X-IIR is more preferable. Further, IIR and X-IIR may be used alone or in combination depending on the purpose and use of the anti-vibration rubber composition.

(B component)
In the vibration-proof rubber composition of the present embodiment, the peak of the loss tangent tan δ is in the temperature range of 0 ° C. or lower (that is, on the low temperature side) in the component A, and in the temperature range of 0 to 60 ° C. (that is, on the high temperature side). B composed of an amorphous α-olefin copolymer from the viewpoint of increasing the loss tangent tan δ in a wide temperature range of 0 ° C., 20 ° C., and 40 ° C. by combining the B component in which the peak of the loss tangent tan δ exists. Contains ingredients. The component B is composed of an amorphous α-olefin copolymer, that is, because it is an α-olefin copolymer, it is highly compatible with the component A composed of butyl rubber, which is an olefin rubber, and is non-component. Since it is crystalline, it is easily mixed with the A component. Since the crystalline α-olefin has a melting point even if it is an α-olefin, the mixture is poorly mixed unless it is kneaded at a temperature equal to or higher than the melting point, and the compression set of the obtained vibration-proof rubber composition becomes large.

Regarding the "amorphous α-olefin copolymer", "amorphous" means that there is no crystallinity, which is confirmed by the absence of a clear melting point. The absence of a clear melting point means that no melting peak is observed when the temperature is raised at 10 ° C./min in a nitrogen gas atmosphere in differential scanning calorimetry (hereinafter, also referred to as DSC). Specifically, using a DSC (for example, DSC822 manufactured by Mettler-Toledo), 7 mg of the sample is heated at 10 ° C./min from room temperature (25 ° C.) to 200 ° C. in a nitrogen gas stream (40 mL / min) atmosphere. And hold for 5 minutes to completely melt the sample, then cool from 200 ° C to -50 ° C at 10 ° C / min, hold at -50 ° C for 5 minutes, then from -50 ° C to 200 ° C at 10 ° C. When the temperature of the melting peak that appears when the temperature is raised again at / min (that is, at the time of the second temperature rise) is defined as the melting point, it means that the melting peak is not recognized.

The "α-olefin copolymer" refers to a copolymer of two or more types of α-olefins. Here, "α-olefin" is a general term for aliphatic unsaturated hydrocarbons in which a double bond is located between _{the terminal carbon C 1} and the adjacent carbon C _2. The α-olefin copolymer is one of two or more types of α-olefins that are copolymerized from the viewpoint of increasing loss positive tan δ in a wide temperature range of 0 ° C, 20 ° C, and 40 ° C. It is preferable that the −olefin is a 4-methyl-1-pentene / α-olefin (excluding 4-methyl-1-pentene) copolymer in which 4-methyl-1-pentene is used.

(Mass ratio of A component and B component)
Mass ratio of A component and B component A: B adjusts the ratio of the combination of the peak of the loss tangent tan δ on the low temperature side derived from the component A and the peak of the loss tangent tan δ on the high temperature side derived from the component B. Therefore, from the viewpoint of increasing the loss tangent tan δ in a wide temperature range of 0 ° C., 20 ° C., and 40 ° C., the range is 90:10 to 65:35, preferably 90:10 to 70:30. ..

(C component)
The anti-vibration rubber composition of the present embodiment shifts the peak of the loss tangent tan δ on the low temperature side derived from the component A to the high temperature side, and increases the loss tangent tan δ on the high temperature side derived from the component B. , 0 ° C., 20 ° C., and 40 ° C., from the viewpoint of increasing the loss tangent tan δ, contains a C component consisting of at least one of a hydrogenated non-polar hydrocarbon resin and a terpene-based hydrocarbon resin.

Regarding "hydrogenated non-polar hydrocarbon resin", "hydrogenation" means that hydrogen is added. "Non-polar" is a synonym for "polar" and does not mean that it has no polarity. Specifically, polar functional groups (polar functional groups such as hydroxy groups, carbonyls). It means that it does not include (such as a group). "Hydrocarbon resin" refers to a resin composed only of carbon and hydrogen. Preferable examples of the hydrogenated non-polar hydrocarbon resin include an alicyclic saturated hydrocarbon resin and a hydrogenated alicyclic / aromatic copolymerized hydrocarbon resin. The "terpene-based hydrocarbon resin" refers to a hydrocarbon resin containing "terpene", which is a hydrocarbon having isoprene as a constituent unit. The hydrogenated non-polar hydrocarbon resin and the terpene-based hydrocarbon resin may be used alone or in combination. The hydrogenated non-polar hydrocarbon resin and the terpene-based hydrocarbon resin are not particularly limited, and commercially available ones having a melting point of about 90 to 150 ° C. are preferably used.

(Content of C component)
The anti-vibration rubber composition of the present embodiment has a loss in a wide temperature range of 0 ° C., 20 ° C., and 40 ° C. by shifting the peak of the loss tangent tan δ on the low temperature side derived from the component A to the high temperature side. From the viewpoint of increasing the tangent tan δ, the content of the C component is preferably 10 parts by mass or more and 50 parts by mass or less with respect to the total content of the A component and the B component of 100 parts by mass. Specifically, the content of the C component is preferably 10 parts by mass or more, more preferably 15 parts by mass or more, from the viewpoint of enhancing the effect of shifting the peak of the loss tangent tan δ on the low temperature side to the high temperature side. Further, from the viewpoint of suppressing the hardness at low temperature from becoming too high by setting the position of the peak temperature of the loss tangent tan δ to 0 ° C. or lower, 50 parts by mass or less is preferable, and 40 parts by mass or less is more preferable.

(Other ingredients)
The anti-vibration rubber composition of the present embodiment has a filler, a vulcanizing agent, a processing aid, and a plasticizer generally used in the rubber composition as other components other than the A component, the B component, and the C component. Agents, softeners, anti-aging agents, coupling agents, colorants, heat radiating materials, conductive materials and the like can be included. The filler is not particularly limited, but carbon black, calcined clay and the like are preferably mentioned from the viewpoint of high reinforcing property and small compression set. The vulcanizing agent is not particularly limited, but in the case of X-IIR, zinc oxide, dithiocarbamic acid-based vulcanization accelerator and the like are preferably mentioned from the viewpoint of good balance of strength, compression set, vulcanization rate and the like. Be done. For the same reason, in the case of IIR, low sulfur vulcanization, sulfur-free vulcanization (sulfur donor vulcanization) and the like are preferably mentioned. As the processing aid, stearic acid or the like is preferably mentioned from the viewpoint that it is effective in a small amount and has little influence on the physical properties.

[Characteristics of anti-vibration rubber composition]
(Loss tangent tan δ in dynamic viscoelasticity measurement)
The anti-viscoelastic rubber composition of the present embodiment contains the above-mentioned A component, B component, and C component, and the mass ratio A: B of the A component and the B component is in the range of 90:10 to 65:35. Therefore, the loss tangent tan δ obtained in the dynamic viscoelasticity measurement under the three conditions of 0 ° C. and 5 Hz, 20 ° C. and 5 Hz, and 40 ° C. and 5 Hz is 0.40 or more, and all of them are 0. It is preferably 50 or more. Therefore, the anti-vibration rubber composition of the present embodiment has a loss tangent tan δ of 0.40 or more, preferably 0.40 or more, in a wide temperature range of 0 ° C., 20 ° C., and 40 ° C. even at a low frequency of 5 Hz. Both show high damping performance of 0.50 or more.

The anti-vibration rubber composition of the present embodiment has a difference between the loss tangent tan δ obtained in the dynamic viscoelasticity measurement under the three conditions of 0 ° C. and 5 Hz, 20 ° C. and 5 Hz, and 40 ° C. and 5 Hz. Is 0.40 or less, and it is preferable that both are 0.30 or less. In such a rubber composition for vibration isolation, the difference between the loss tangent tan δ is 0.40 or less, preferably any of them, in a wide temperature range of 0 ° C., 20 ° C., and 40 ° C. even at a low frequency of 5 Hz. It shows stable damping performance of 0.30 or less. Here, "the difference between the loss tangent tan δ is any" means the difference in the loss tangent tan δ between the two conditions of all combinations selected from the above three conditions (that is, the number of differences in the loss tangent tan δ). Means all of 3). That is, the difference between the maximum value and the minimum value of the loss tangent tan δ under the above three conditions is 0.40 or less, and preferably 0.30 or less.

The anti-vibration rubber composition of the present embodiment has dynamic viscoelasticity under four conditions in which the conditions of 0 ° C. and 5 Hz, 20 ° C. and 5 Hz, and 40 ° C. and 5 Hz are further added to the conditions of 20 ° C. and 100 Hz. The loss tangent tan δ obtained in the elastic measurement is preferably 0.40 or more, more preferably 0.50 or more, and the difference between the loss tangent tan δ under the above four conditions is any. Is preferably 0.40 or less, and more preferably 0.30 or less in each case. Such a rubber composition for vibration isolation has a loss tangent tan δ of 0.40 or more, preferably 0, in a wide low frequency range of 5 Hz and 100 Hz and a wide temperature range of 0 ° C., 20 ° C., and 40 ° C. It exhibits a higher damping performance of .50 or more, and a more stable damping performance with a difference between the loss tangents tan δ of 0.40 or less, preferably 0.30 or less. Here, "the difference between the loss tangent tan δ is any" means the difference in the loss tangent tan δ between the two conditions of all combinations selected from the above four conditions (that is, the number of differences in the loss tangent tan δ). Means all of 6). That is, the difference between the maximum value and the minimum value of the loss tangent tan δ under the above four conditions is preferably 0.40 or less, and more preferably 0.30 or less.

The anti-viscoelastic rubber composition of the present embodiment has four conditions of 0 ° C. and 5 Hz, 20 ° C. and 5 Hz, 40 ° C. and 5 Hz, and 20 ° C. and 100 Hz, and further added conditions of −10 ° C. and 5 Hz 5 The loss tangent tan δ obtained in the dynamic viscoelasticity measurement under one condition is more preferably 0.40 or more, further preferably 0.50 or more, and the loss tangent tan δ under the above five conditions is more preferable. The difference between the two is more preferably 0.40 or less, and further preferably 0.30 or less. The anti-vibration rubber composition has a loss tangent tan δ of 0.40 or more in a wide low frequency range of 5 Hz and 100 Hz and a wider temperature range of -10 ° C, 0 ° C, 20 ° C, and 40 ° C. Preferably, all of them show a higher damping performance of 0.50 or more, and the difference between the loss tangents tan δ is 0.40 or less, preferably 0.30 or less, and more stable damping performance is shown. Here, "the difference between the loss tangent tan δ is any" means the difference in the loss tangent tan δ between the two conditions of all combinations selected from the above five conditions (that is, the number of differences in the loss tangent tan δ). Means all of 10). That is, the difference between the maximum value and the minimum value of the loss tangent tan δ under the above five conditions is more preferably 0.40 or less, and further preferably 0.30 or less.

(Compressive permanent strain)
The anti-vibration rubber composition of the present embodiment contains the above-mentioned A component, B component, and C component, and the mass ratio A: B of the A component and the B component is in the range of 90:10 to 65:35. Therefore, the permanent compression strain after 25% compression at 70 ° C. and 24 hours is 30% or less, and the vibration isolation performance (damping performance) has high stability over a long period of time. The anti-vibration rubber composition of the present embodiment has a permanent compression strain of 30% or less, preferably 20% or less, after 25% compression, from the viewpoint of maintaining high stability of damping performance over a long period of time. ..

[Manufacturing method of anti-vibration rubber composition]
The method for producing the anti-vibration rubber composition of the present embodiment is not particularly limited, and a general method for producing the anti-vibration rubber composition is used. For example, a predetermined amount of A component, B component, C component, and other components (filler, processing aid, vulcanizer, etc.) are sequentially added to an open roll or a closed kneader (for example, Banbury mixer, kneader, etc.). Add and mix. At this time, it is preferable to raise the temperature of the rubber dough composed of the A component and the B component to a temperature equal to or higher than the melting point of the C component so that the C component is sufficiently melted. Next, the rubber composition for kneading and vibration isolation obtained by lowering the rubber temperature so as not to react during kneading, adding a vulcanizing agent and a vulcanization accelerator as appropriate, and mixing with an open roll or the like. A rubber composition for cross-linking vibration isolation is obtained by vulcanizing the product at 140 to 190 ° C. for 1 to 30 minutes.

1. 1. Preparation of Anti-Vibration Rubber Composition [Example 1]
The parts A, processing aid, B component, C component, and filler shown in Table 1 are sequentially added to a 10 L kneader and kneaded until the temperature of the rubber composition reaches 110 ° C. to prepare the A kneaded composition. Obtained. The obtained A kneading composition is put into a 12-inch open roll, a vulcanizing agent and a vulcanization accelerator are put into it, and then kneaded at about 50 ° C. for 10 minutes to prepare a rubber composition for vibration isolation. bottom. Next, the obtained anti-vibration rubber composition was vulcanized at 160 ° C. for 20 minutes to prepare a cross-linked anti-vibration rubber composition.

[Examples 2 to 19, Comparative Examples 1 to 11]
As shown in Tables 1 to 6, the rubber composition was prepared according to Example 1 except that the blending amount of each component was changed and the discharge temperature of the kneader kneading was set to be equal to or higher than the melting point of each C component. Made. As for the comparative example containing no C component, it was kneaded until the temperature reached 110 ° C. in the same manner as in Example 1 to obtain an A kneading composition. Next, the obtained anti-vibration rubber composition was vulcanized in the same manner as in Example 1 to prepare a cross-linked anti-vibration rubber composition. However, Examples 2 and 16 and Comparative Examples 1 and 2 were vulcanized at 170 ° C. for 30 minutes.

Here, regarding the A component in Tables 1 to 6, "Cl-IIR" indicates chlorinated butyl rubber (chlorobutyl 1066 manufactured by JSR Corporation), "IIR" indicates butyl rubber (butyl 268 manufactured by JSR Corporation), and "EPDM". "" Indicates ethylene propylene diene rubber (EP-33 manufactured by JSR Corporation), and "NBR" indicates acrylonitrile butadiene rubber (N230 manufactured by JSR Corporation, acrylonitrile content of 35% by mass).

Regarding the B component in Tables 1 to 6, "acrystalline α-olefin copolymer" is an amorphous 4-methyl-1-pentene / α-olefin copolymer (EP1001, manufactured by Mitsui Chemicals Co., Ltd., clear). (There is no melting point), and the "crystalline α-olefin copolymer" is a crystalline 4-methyl-1-pentene / α-olefin copolymer (EP1013 manufactured by Mitsui Kagaku Co., Ltd., melting point 121 ° C. and 134 ° C.). ), "Hydrogenized styrene-butadiene copolymer" indicates an amorphous styrene-butadiene copolymer (SOE1605 manufactured by Asahi Kasei Co., Ltd., no clear melting point exists), and "polyethylene" indicates crystalline polyethylene (Sumitomo Sei). Frosen UF manufactured by Ka Co., Ltd., having a melting point of 104 ° C.) is shown.

Regarding the C component in Tables 1 to 6, "hydrocarbon non-polar hydrocarbon resin a" indicates an alicyclic saturated hydrocarbon resin (Arcon P90 manufactured by Arakawa Chemical Industry Co., Ltd., melting point 90 ° C.), and "hydrocarbonation". "Non-polar hydrocarbon resin b" indicates an alicyclic saturated hydrocarbon resin (Arcon P100 manufactured by Arakawa Chemical Industry Co., Ltd., melting point is 100 ° C.), and "hydrogenated non-polar hydrocarbon resin c" is an alicyclic saturated hydrocarbon. The resin (Arcon P140 manufactured by Arakawa Chemical Industry Co., Ltd., melting point 140 ° C.) is shown, and the "hydrocarbon nonpolar hydrocarbon resin d" is a hydrogenated hydrocarbon resin (T-REZ manufactured by JXTG Holdings Co., Ltd., melting point 103 ° C.). ), "Terpen-based resin a" indicates an aromatic-modified terupene resin (YS Polystar TO-125 manufactured by Yasuhara Chemical Co., Ltd., melting point 125 ° C.), and "terpene-based resin b" indicates a terpen resin (YS manufactured by Yasuhara Chemical Co., Ltd.). Resin PX1000, melting point 100 ° C), "non-hydrocarbon resin a" indicates C5-C9 hydrocarbon resin (Petrotac 100V manufactured by Toso Co., Ltd., melting point 96 ° C), "non-hydrocarboned" "Hydrogen resin b" indicates a C9-based hydrocarbon resin (Petcol 100T manufactured by Toso Co., Ltd., melting point 95 ° C.), and "Rodin ester resin" refers to Pine Crystal KE-100 (melting point 100 ° C.) manufactured by Arakawa Chemical Industry Co., Ltd. show.

Regarding the fillers in Tables 1 to 6, "SRF" indicates soft carbon type medium reinforcing carbon black (Tokai Carbon Co., Ltd. Seest S) having low particle hardness, and "HAF" indicates particle hardness. It refers to a hard carbon type carbon black with high abrasion resistance (Seast 3H manufactured by Tokai Carbon Co., Ltd.), and "baked clay" refers to Burgess KE manufactured by Shiraishi Calcium Co., Ltd.

Regarding the processing aids in Tables 1 to 6, "stearic acid" indicates Lunac S-70V manufactured by Kao Corporation.

Regarding the sulfides in Tables 1 to 6, "zinc oxide" indicates one kind of zinc flower manufactured by Sakai Chemical Co., Ltd., "sulfur" indicates Sarfax A manufactured by Tsurumi Chemical Industry Co., Ltd., and "ZDEC" indicates diethyl. Zinc dithiocarbamate (Noxeller Ez manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.), "DTDM" indicates 4,4'-dithiodimorpholin (Barnock R manufactured by Ouchi Shinko Kagaku Kogyo Co., Ltd.), and "CBS" indicates N-cyclohexyl-2-benzothiazolyl sulphenamide (Noxeller Cz manufactured by Ouchi Shinko Co., Ltd.) is shown, and "dicumyl peroxide" is Park Mill D manufactured by Nichiyu Co., Ltd.

2. Evaluation of characteristics of anti-vibration rubber composition As the characteristics of the cross-linked anti-vibration rubber composition obtained above, hardness, breaking strength, compression set, and loss tangent tan δ were measured as follows, and the results are shown in the table below. It is summarized in 1-6.

(hardness)
In accordance with JIS K6253: 2012, a type A durometer (P-2A manufactured by Polymer Meter Co., Ltd.) was used to read the indicated value 3 seconds after the needle was pressed.

(Breaking strength)
A sheet having a thickness of 2 mm was formed and punched to prepare a JIS No. 3 dumbbell, which was used as a measurement sample. Strength when the measured sample breaks by pulling at a tensile speed of 500 mm / min using a tensile tester (Autograph AG-1 manufactured by Shimadzu Corporation) in a manner conforming to JIS K6251: 2017 (breaking strength: unit) MPa) was measured.

(Compressive permanent strain)
A measurement sample having a diameter of 29 mm and a thickness of 12.5 mm was prepared. The measurement sample is compressed at 70 ° C. for 24 hours at a compression rate of 25% in the thickness direction, then taken out into a room at room temperature (25 ° C.) and left for 30 minutes in accordance with JIS K6262: 2013. Measure the thickness of, and use the following formula (1)
CS = 100 × (t ₀ −t ₂ ) / (t ₀ −t ₁ ) ・ ・ ・ (1)
In equation (1)
CS: Compressed permanent strain (%)
t ₀ : Original thickness of measurement sample (mm)
t ₁ : Thickness of the measurement sample when compressed (mm)
t ₂ : Thickness (mm) of the measurement sample 30 minutes after being left at room temperature
The compression set was calculated.

(Loss tangent tan δ)
The dynamic viscoelasticity of the measurement sample was measured basically in accordance with JIS K6394: 2007. Detailed measurement conditions
Measurement sample: length 20 mm x width 5 mm x thickness 2 mm
Distance between chucks: 15 mm
Measurement mode: Tension initial strain: 12.5% elongation Amplitude: ± 2 μm (0.013%)
Temperature rise rate: 3 ° C / min Measurement temperature / frequency: 0 ° C / 5Hz, 20 ° C / 5Hz, 40 ° C / 5Hz, 20 ° C / 100hz, or -10 ° C / 5Hz
Measuring machine: Rheogel-E4000 manufactured by UBM Co., Ltd.
And said.

With reference to Table 1, Examples 1 and 2 show A component composed of chlorinated butyl rubber or butyl rubber which is a butyl rubber, B component composed of an amorphous α-olefin copolymer, and hydrogenated non-polar hydrocarbon. Since it is a rubber composition for vibration isolation having a C component made of a resin and having a mass ratio A: B of the A component and the B component in the range of 90:10 to 65:35, the target characteristics (0 ° C. and The loss tangent tan δ under the three conditions of 5 Hz, 20 ° C. and 5 Hz, and 40 ° C. and 5 Hz is 0.4 or more, and the difference between the loss tangent tan δ is 0.4 or less, and the same applies hereinafter). I was able to achieve it. In the anti-vibration rubber compositions of Comparative Examples 1 and 2, since the component A was not a butyl rubber, the loss tangent tan δ under the above three conditions was less than 0.4. Since the anti-vibration rubber composition of Comparative Example 3 did not have the C component, the loss tangent tan δ under the conditions of 0 ° C. and 5 Hz and 20 ° C. and 5 Hz was less than 0.4. Since the anti-vibration rubber composition of Comparative Example 4 does not have the B component, the loss tangent tan δ at 40 ° C. and 5 Hz is less than 0.4, and the loss tangent tan δ at 0 ° C. and 5 Hz and 40 ° C. Moreover, the difference in loss tangent tan δ from the condition of 5 Hz was extremely large.

With reference to Table 2, Example 1 comprises component A composed of chlorinated butyl rubber, which is a butyl rubber, component B composed of an amorphous α-olefin copolymer, and C composed of a hydrogenated non-polar hydrocarbon resin. Since the rubber composition for vibration isolation has components and the mass ratio A: B of component A and component B is in the range of 90:10 to 65:35, the target characteristics could be achieved. The anti-vibration rubber compositions of Comparative Examples 5 to 7 could not achieve the target characteristics because the B component was not an amorphous α-olefin copolymer.

With reference to Table 3, Examples 1 and 3 to 5 show a component A composed of chlorinated butyl rubber, which is a butyl rubber, a component B composed of an amorphous α-olefin copolymer, and a hydrogenated non-polar hydrocarbon. Since it is a rubber composition for vibration isolation having a C component made of a resin and having a mass ratio A: B of the A component and the B component in the range of 90:10 to 65:35, the target characteristics could be achieved. .. Examples 6 and 7 have an A component made of chlorinated butyl rubber, which is a butyl rubber, a B component made of an amorphous α-olefin copolymer, and a C component made of a terpene resin, and the A component and the B component. Since the rubber composition for vibration isolation has a mass ratio A: B with the component in the range of 90:10 to 65:35, the target characteristics could be achieved. Example 8 has a component A made of chlorinated butyl rubber, which is a butyl rubber, a component B made of an amorphous α-olefin copolymer, and a component C made of a hydrogenated non-polar hydrocarbon resin and a terpene resin. However, since the rubber composition for vibration isolation has a mass ratio A: B of component A and component B in the range of 90:10 to 65:35, the target characteristics could be achieved. The anti-vibration rubber compositions of Comparative Examples 8 to 10 could not achieve the target characteristics because the C component was neither a hydrogenated non-polar hydrocarbon resin nor a terpene resin.

With reference to Table 4, Examples 1, 9 and 10 show A component composed of chlorinated butyl rubber which is a butyl rubber, B component composed of an amorphous α-olefin copolymer, and hydrogenated non-polar hydrocarbon. Since it is a rubber composition for vibration isolation having a C component made of a resin and having a mass ratio A: B of the A component and the B component in the range of 90:10 to 65:35, carbon black (as a filler) The target characteristics could be achieved regardless of whether the SRF and HAF) or the calcined clay was used. Here, carbon black was suitable as the filler from the viewpoint of high hardness and breaking characteristics.

With reference to Table 5, Examples 1 and 11 to 15 show a component A composed of chlorinated butyl rubber, which is a butyl rubber, a component B composed of an amorphous α-olefin copolymer, and a hydrogenated non-polar hydrocarbon. It has a C component made of resin, and the mass ratio A: B of the A component and the B component is in the range of 90:10 to 65:35, and the total content of the A component and the B component is 100 parts by mass. On the other hand, since the rubber composition for vibration isolation has a C component content of 10 parts by mass or more and 50 parts by mass or less, the target characteristics could be achieved.

With reference to Table 6, Examples 1 and 16-19 show A component composed of chlorinated butyl rubber or butyl rubber which is a butyl rubber, B component composed of an amorphous α-olefin copolymer, and hydrogenated non-polarity. Since it has a C component made of a hydrocarbon resin and the mass ratio A: B of the A component and the B component is in the range of 90:10 to 65:35, the target characteristics could be achieved. The anti-vibration rubber composition of Comparative Example 11 could not achieve the target characteristics because the mass ratio A: B of the component A and the component B was out of the range of 90:10 to 65:35.

The embodiments and examples disclosed this time should be considered to be exemplary and not restrictive in all respects. The scope of the present invention is shown by the scope of claims rather than the above description, and it is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

Claims (5)

It contains a component A made of butyl rubber, a component B made of an amorphous α-olefin copolymer, and a component C made of at least one of a hydrogenated non-polar hydrocarbon resin and a terpene hydrocarbon resin. ,
A rubber composition for vibration isolation in which the mass ratio A: B of the component A to the component B is in the range of 90:10 to 65:35. The loss tangent tan δ obtained in the dynamic viscoelasticity measurement under the three conditions of 0 ° C. and 5 Hz, 20 ° C. and 5 Hz, and 40 ° C. and 5 Hz is 0.40 or more, and the difference between the loss tangent tan δ is greater than or equal to 0.40. The anti-viscoelastic rubber composition according to claim 1, wherein both are 0.40 or less. The anti-vibration rubber composition according to claim 1 or 2, wherein the component A is at least one of butyl rubber and halogenated butyl rubber. The method according to any one of claims 1 to 3, wherein the content of the C component is 10 parts by mass or more and 50 parts by mass or less with respect to the total content of the A component and the B component of 100 parts by mass. Anti-vibration rubber composition. The anti-vibration rubber composition according to any one of claims 1 to 4, wherein the compression set after 25% compression at 70 ° C. and 24 hours is 30% or less.